Methyl acetate is an important organic chemical material and solvent. Methyl acetate can be used to produce acetic acid and its derivatives, such as acetic anhydride, vinyl acetate and the like. In present industrial production, acetic acid has been mainly prepared by the Monsanto and BP homogeneous carbonylation of methanol, in which the noble metal catalysts containing Rh or Ir and the corrosive catalyst promoters CH3I have been used [J. Catal. 245 (2007) 110˜123]. Methyl acetate can be used for producing ethanol by the hydrogenation reduction [ChemSusChem 3 (2010) 1192˜1199]. The octane value of ethanol is higher than gasoline, and ethanol can burn completely in the combustion engine so that ethanol itself or its mixture with gasoline both can be used as the automobile fuels. Now ethanol gasoline with the ethanol content range from 5% to 85% has been commercially used. Mixing ethanol into gasoline also can reduce the greenhouse gas emission. Currently ethanol has been industrially produced by two main ways which are the biological fermentation of corn or sugarcane and the hydration of ethylene. Biological fermentation to produce ethanol generally only can produce a low concentration ethanol which is about 14%. To obtain the fuel ethanol, the usage of rectification process became necessary, which need the heavy investment and the high energy consumption. Besides ethanol productivity of the biological fermentation is limited to avoid threatening food security because the biological fermentation is at the expense of economic crops, such as grain. The hydration of ethylene is losing its economic competitiveness with the exhaustion of oil resources and the price rise of ethylene, since ethylene is obtained mainly from petrochemical industry. In addition, methyl acetate can be used as a green solvent which is widely applied in the field of textile, spices, medicine, food and the like. Methyl acetate also can be obtained by the carbonylation of dimethyl ether and carbon monoxide, and dimethyl ether can be prepared by the dehydration of methanol or the one-step synthesis from syngas, so methyl acetate can be seen as a derivative of syngas. Industrial synthesis technology of syngas is very mature by the gasification of non-petroleum sources, such as coal, natural gas, biomass and the like.
So far, among the catalysts for preparing methyl acetate by the carbonylation of dimethyl ether which have been reported, mordenite with 8-membered ring and 10-membered ring is the most studied and the most active. Iglesia et al. found that the active centers of catalysis carbonylation locate at Bronsted acid sites of 8-membered ring [J. Am. Chem. Soc. 129 (2007) 4919˜4924] and the selectivity for methyl acetate was higher than 99%, while they did not study the life and inactivation of the catalysts in details. The research work of Wenjie Shen et al. indicated that the stability of the carbonylation of dimethyl ether could be improved significantly by pre-adsorbing pyridine in mordenite [Chin. J. Catal. 31 (2010) 729˜738], and the yield of methyl acetate was kept at about 30% after reacting for 48 h at 200° C. Pyridine located in 12-membered ring restricts the generation of carbon deposits in 12-membered ring, and acid sites of 8-membered ring are not affected. However, pyridine adsorbed in mordenite will desorb slowly under the reaction conditions, resulting in the decline of catalyst activity, catalyst stability and catalyst life with the slow increase of carbon deposits, which seriously restrict the large-scale application in industrial production.